In many fields of communication, a suitable antenna is desired. Flat, robust and lightweight antennas are desired for many applications, especially in the millimeter wave range with frequencies around 30-300 GHz, in particular 60 GHz and 70/80 GHz. Such an antenna should further be inexpensive to manufacture and still have good electric properties with respect to bandwidth, loss and matching.
Such an antenna should preferably have tightly integrated RF-circuits and duplex filters, beyond connecting parts with waveguide interface.
One way to accomplish such antennas is by using a so-called substrate integrated waveguide, SIW, as a base, which has many advantages. SIW antennas with multilayer boards having a SIW distribution network, hierarchal arrangement to allow equal length of propagation to all elements, and additional circuit board layers that contain radiating structures, are previously known. However, such structures suffer from tolerance problems and high manufacturing costs. Other previously known antennas based on SIW technology also suffer from narrow-banded functionality.
There is thus a desire to provide an antenna arrangement based on SIW technology, with improvements with regards to the mentioned issues.